NO.PZ2018070201000064
问题如下：
Eunice, an analyst from an investment company, recently made the following statements about an equally-weighted portfolio consisting of a large number of assets：
Statement 1: Average variance of the individual assets contributes the most to the volatility of the portfolio.
Statement 2: Standard deviation of the individual assets contributes the most to the volatility of the portfolio.
Statement 3: Average covariance between all pairs of assets contributes the most to the volatility of the portfolio.
Which statement is most correct?
选项：
A.
Statement 1.
B.
Statement 2.
C.
Statement 3.
解释：
C is correct.
As the number of assets in the same weighting portfolio increases, the co-movement between assets also increases. As the number of assets contained in the equally weighted portfolio increases, the contribution of each individual asset's variance to portfolio volatility decreases.The following equation for the variance of an equally weighted portfolio illustrates these points:
如果不比较程度，这个相同权重的大资产组合的影响因素就是平均标准差和平均协方差，表述是：Average stadard deviation 和 average covariance。对吗？
